Modern diagnostic radiology assures faster, more precise diagnosis and enables monitoring of a large proportion of diseases by using of ionising radiations such as X-rays, gamma rays, beta rays and electrons. The inherent properties of these ionising radiations provide many diagnostic benefits but also prone to cause the potential health problems. It is well established that the effects of these radiation are cumulative and lead to increased incidence of cancers, cell deaths and genetic damages. Therefore, protection against ionising radiation has achieved central importance to avoid health related problems in patients and in radiation laboratory technicians.
In order to ensure minimal X-ray radiation penetration, individuals who come in contact with X-rays are required to wear lead-lined protection wear, such as aprons, gloves, goggles, and thyroid protection. Three different categories of wearable protection include total (100%) lead-lined clothing, lead composite clothing, and non-lead clothing. While the total lead lined clothing has the highest protection against high and scattered low energy radiation, it is inflexible, extremely heavy (15.1 lbs/sq yard) and can cause severe neck and back problems for individuals who wear them for many hours. Furthermore, lead has been recognized as major environmental pollutant, including the lead used for radiation shielding in radiotherapy.
Therefore, in accordance with the present disclosure there is envisaged a nontoxic material having equivalent radiation shielding capability as lead.
Objects:
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to ameliorate one or more problems of the prior art or to at least provide a useful alternative.
It is another of the present disclosure to provide bimetallic nanofibers which can be used as a substitute for lead in X-ray shielding application.
It is yet another object of the present disclosure to provide a process for synthesis of bimetallic nanofibers.
It is still another object of the present disclosure to provide an X-ray shielding article.
It is a further object of the present disclosure to provide an X-ray shielding composition having medicinal and/or cosmetic applications.
In accordance with one aspect of the present disclosure there is provided a process for synthesis of barium bismuth sulfide nanofibers, said process comprising the following steps;                a. dissolving barium nitrate, bismuth nitrate pentahydrate and thiourea in a solvent system to obtain a dispersion containing complex of barium bismuth sulfide; and        b. mixing at least one surfactant in the dispersion under continuous agitation to obtain a homogeneous mixture;        c. heating the homogeneous mixture at a temperature ranging between 120° C. and 180° C. in an apparatus for 24 hours followed by cooling at a temperature ranging between 20° C. and 30° C. to obtain a precipitate; and        d. washing the precipitate by employing at least one solvent selected from the group consisting of water, ethanol, methanol, isopropanol and acetone to obtain nanofibers of barium bismuth sulfide.        
Typically, the solvent system is a combination of ethylene glycol and water at a proportion ranging between 1:1 and 3:1.
Typically, the surfactant is at least one selected from the group consisting of cetyl trimethylammonium bromide, polyvinyl alcohol and polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether.
Typically, the average diameter of the nanofibers is between 20 nm and 50 nm.
Typically, the average length of the nanofibers is between of 1 μm and 3 μm.
Typically, Barium bismuth sulfide nanofibers are characterized by (a) diameter of 20 nm to 50 nm and (b) the length of 1 μm to 3 μm and the X-Ray diffraction pattern having 2θ values at 28.58, 24.95, 46.52, 31.82, 52.7, 45.53, 32.87, 39.89 and 35.48.
In accordance with another aspect of the present disclosure there is provided a coating composition comprising barium bismuth sulfide nanofibers in an amount ranging between 10% and 60%, preferably between 20% and 40% of the total mass of said composition, at least one thinner and at least one color guard.
Typically, the thinner is at least one selected, from the group consisting of ethyl methyl ketone, amyl acetate and acetone in an amount ranging 10% and 90%, preferably between 20% and 80% of the total mass of said composition.
Typically, the color guard is at least one selected from the group consisting of epoxy, nitrocellulose and ethyl cellulose in an amount ranging between 5% and 30%, preferably between 8% and 12%.
In accordance with another aspect of the present disclosure there is provided a process for preparation of a coating composition comprising barium bismuth sulfide nanofibers; said process comprising the following steps:                a. milling barium bismuth sulfide nanofibers to obtain a mass; and        b. adding at least one color guard and at least one thinner into the mass followed by mixing to obtain a coating composition.        
Typically, milling is carried out for a time period ranging between 12 hours and 48 hours, preferably between 20 hours and 25 hours.
In accordance with another aspect of the present disclosure there is provided a process for the preparation of an X-ray shielding article; said process comprising the following steps:                a. contacting said article with coating composition comprising barium bismuth sulfide nanofibers, at least one thinner and at least one, color guard to obtain a coated article; and        b. annealing the coated article by hot air at a temperature ranging between 50° C. and 60° C. for a time period ranging between 0.5 and 2 min. to obtain X-ray shielding article.        
Typically, the amount of barium bismuth sulphide nanaofibers is in the range between 10% and 60%, preferably between 20% and 40% of the total mass of said composition.
Typically, the article is at least one selected from the group consisting of aprons, gowns, scrubs, uniforms, gloves, caps, masks, curtains, sheets, fabrics, shoe covers, drapes, surgical pads, protective screens, thyroid collars, thyroid shields, desks, drawers, rooms, walls, partitions, panels, tables, chairs and cabinets.
Typically, the article is contacted with coating composition by at least one method selected from the group comprising applying, spraying, dipping, incorporating brushing and painting. Typically, the color guard is at least one selected from the group consisting of epoxy, nitrocellulose and ethyl cellulose in an amount ranging between 5% and 30%, preferably between 8% and 12% of the total mass of said composition.
Typically, the thinner is at least one selected from the group consisting of Ethyl methyl ketone, amyl acetate and acetone in an amount ranging 10% and 90%, preferably between 20% and 80% of the total mass of said composition.
In accordance with another aspect of the present disclosure there is provided an X-ray shielding composition comprising barium bismuth sulfide nanofibers, in the range of 20% and 30% of the total mass of the said composition and at least one pharmaceutically acceptable excipient.
Typically, the excipient is at least one selected from the group consisting of gelling agent, emulsifiers, surfactants, humectants, preservatives, antioxidants, opacifiers, colorants, propellants, gelling agents, waxes and oils.
Typically, said X-ray shielding composition is in a form selected from the group consisting of gels, creams, lotions, sprays and ointments.